Identify the part which contains an error.
A good employee (A) is one (B) which is (C) punctual and efficient. (D)

Correct option is C

Option (c) contains an error.
• The sentence refers to a person (“employee”).
• For persons, the correct relative pronoun is who/that, not which.
• “Which” is generally used for things/animals, not for human beings in such structures.
• So “which is punctual and efficient” should be corrected to who is punctual and efficient.
Correct sentence:
• A good employee is one who is punctual and efficient.
Grammatical Rule Used (English):
• Relative pronouns:
– who/whom/whose for persons
– which for things/animals
– that can be used for persons or things in many cases
Grammatical Rule Used (Hindi):
• Relative pronoun का चयन noun के अनुसार होता है:
– व्यक्ति (person) के लिए who
– वस्तु/चीज़ (thing) के लिए which
• “employee” व्यक्ति है, इसलिए “which” गलत है; सही “who” होगा।